1. Field of Invention
This invention relates to reverse osmosis water systems and is particularly directed to improved reverse osmosis water systems having a manual Start-Up Bypass mechanism and an automatic shut-off valve, and storage reservoir.
2. Prior Art
As is well known, reverse osmosis water purification is accomplished by applying impure water, under pressure, to a semi-permeable osmotic membrane to force pure water to flow through the membrane, while leaving the contaminant materials on the input side of the membrane. However, unless constant pressure is maintained on the input side of the membrane, the pure water will tend to flow back through the membrane. Early reverse osmosis systems required a continuous flow of input water in order to maintain such pressure. Obviously, this was extremely wasteful. On the other hand, if the contaminated water, under no pressure, is allowed to remain in contact with the membrane and the pure water is not drawn off promptly, some of the contaminants will also pass through the membrane and, hence, will recontaminate the "pure" water. Many modern reverse osmosis systems solve this problem by including a by-pass system, which allow such recontamination to occur, but which automatically discharge several cups of water before starting to deliver the allegedly purified water to the reservoir. This eliminates the need for continuous flow of input water. However, the quantity of water discharged by the automatic by-pass system may or may not be appropriate. Thus, in many instances, significant amounts of pure water will be wasted, while, in other cases, some contaminated water will be delivered to the pure water reservoir. This problem is found, particularly, in permanently installed water purification systems, such as the so-called "under the counter" systems. Poor reliability has plagued this by-pass system, so that manual by-pass systems are preferred. With so-called "portable" or countertop systems, if applicable, the user is instructed to discard a preliminary amount of water. However, if frequent or repeated uses occur, the user can safely forego the discard in order to save water. Some countertop water purification systems have a hose which is placed in a nearby sink or fastened and terminated at the kitchen faucet aerator for discharging waste water. This is a substantial amount of water during flushing of the membrane and, unfortunately, this can be noisy and annoying during operation of the portable water purification system. Furthermore, even when care is taken to properly position the discharge hose, for example, to direct the flow against the side of the sink to minimize splashing and noise, air bubbles are often carried in the discharge flow and can cause vibrations which will dislocate the hose so that the noise will return or the discharge flow is discharging in a nondesirable location. Another disadvantage of most reverse osmosis water systems lies in the fact that some way must be provided for matching the quantity of input or supply water to the usage of the purified water. If the input supply is unregulated, vast quantities of input water will be discarded wastefully. Permanent or "under-the-counter" systems, and portable or "counter-top" systems usually employ electrical or hydraulic valves and electronic circuitry to sense the level or quantity of water in the reservoir and, as appropriate, to actuate the valve to pass input water to restore the desired level or quantity. Most countertop systems avoid the expense and complexity of such control systems, but usually require that the user regulate the input supply manually. This demands constant visual monitoring of the water level in the reservoir and that the user be physically present to start and stop the flow of input water, as needed. Another problem of prior art countertop water systems has been lack of flexibility in design which has seriously limited the locations in which such systems may be placed. Many carbon filters, previously purchased, utilize costly non-disposable chambers that were satisfying the needs of many, but recently, the desire to combine this treatment with a reverse osmosis filter has left non-disposable carbon chambers abandoned. A design to combine the non-disposable carbon chamber with a reverse osmosis filter is needed.
Another problem of the prior art has been the over use of raw materials in the fabrication of a cabinet to house the portable water purification system. Yet another problem is the antiquated method of collecting the waste water for reuse. A further disadvantage of the prior art is the hose used to connect the water purification system to a separate reservoir. If using a plug to keep the hose clean during storage, a damaged reverse osmosis element could result. As is well known in the field that, if the system is turned "ON" without removing such the hose plug, which protects the hose from contamination during storage, and if the system is turned "OFF" with a differential pressure across the membrane, destruction of the membrane will occur. A "fail safe" plug is needed.
An additional disadvantage of the prior art is that no convenient way of storing the hose which connects the purification system to the reservoir has been provided heretofore. Furthermore, all prior art portable water purification systems have had an easily removable reservoir lid. However, curious minds will open this lid, which allows airborne contaminants into the reservoir. A deterrent is needed to prevent this action. Furthermore, many other disadvantages of prior art water purification systems exist regarding storage of pure water. Due to the chemical composition of the pure water, recontamination occurs when the pure water is stored in a petroleum-based container. Moreover, such reservoirs are difficult to clean, since they usually are integral parts of the housing of the water system. Moreover, there is no barrier to prevent air contamination of the pure water. Finally, pure water entering the storage reservoir makes an annoying sound when falling into the body of pure water within the reservoir.
A search in the United States Patent Office has revealed the following:
______________________________________ U.S. Pat. No. INVENTOR ISSUED ______________________________________ 4,391,712 T. V. Tyler et al Jul. 5, 1983 4,678,565 W. W. Norton Jul. 7, 1987 3,670,892 W. Baerg et al Jun. 20, 1972 4,759,844 M. Lipschultz et al Jul. 26, 1988 4,880,535 B. D. Burrows Nov. 14, 1989 4,049,550 L. Obidniak Sep. 20, 1977 4,609,466 C. W. McCausland et al Sep. 2, 1986 4,744,895 M. A. Gales et al May 17, 1988 ______________________________________
Each of these references is subject to the disadvantages discussed above. Thus, none of the prior art reverse osmosis water systems have been entirely satisfactory.